Police say 36-year-old Curtis Van Dam, of Sioux Center, also is charged with 14 counts of sexual exploitation by a teacher. Jail records say he remained in custody Thursday. His attorney didn't immediately return a call from The Associated Press.

Police say the charges stem from incidents involving numerous children between August 2013 and last month. A news release says the crimes occurred at various locations, including Sioux Center Christian School, where Van Dam worked.

Police began investigating after a complaint was filed alleging inappropriate conduct between Van Dam and a student at the school.